Method of lining a bearing shell



May 6, 1958 N. L. DALTON I 2,833,667

METHOD OF LINING A BEARING'SHELL Filed June 7, 1954 A/oe/ A. Da/zo'nINVENTOR.

A r Tog/v5 Kr nited tates METHOD OF LINING A BEARING SHELL Noel L.Dalton, Houston, Tex.

Application June 7, 1954, Serial No. 434,695

4 Claims. (Cl. 117--5tl) This invention relates to new and usefulimprovements in bearings and methods of making same.

In the manufacture of bearings, such as the bearings for engine shafts,a bearing shell is generally lined with a bearing material such asbabbitt. The babbitt is ordinarily poured on'a tin coated bearing shellto form a predetermined thickness of the babbitt lining. As the babbittcools from its liquid to the solid state after being poured into themetal sleeve or shell, there is a relatively high shrinkage of thebabbitt as compared to the meta] shell and as such shrinkage of thebabbitt occurs, the tin coating is pulled loose from the bearing shellso that the bond between the babbitt and the metal bearing shell isweakened or separated to such an extent that the babbitt flakes out orotherwise fails after relatively short periods of use. Attempts havebeen made to apply the babbitt material by spraying. Material applied byspraying is not subject to the shrinkage Which occurs in poured materialbut no practical way has been heretofore devised to produce an efficientand satisfactory bond between the babbitt material and the bearingshell.

One object of this invention is to provide an improved method ofapplying babbitt material to a bearingshell wherein the babbitt materialis sprayed onto the bearing shell and an eflicient bond between thebabbitt material and the shell is produced.

An object of this invention is to provide a new and improved babbittlined bearing in which the shrinkage of the babbitt metal in the bearingbody member or shell is substantially completely eliminated whereby afailure of the bearing due to an improper bond between the bearing bodymember or shell and the babbitt is prevented.

An important object of this invention is to provide a new and improvedlined bearing and a method of making same wherein an initial layer ofbabbitt is applied in a relatively thin layer to a bearing body memberor shell having a layer of tinning material thereon to fuse the babbittto the tinning material without weakening or damaging the bond betweenthe tinning material and the bearing bodymember.

Another object of this invention is to' provide a new and improvedbearing and the method of making same, wherein the bearing is formed byspraying a relatively thin layer of babbitt material onto a previouslytinned surface on a bearing shell when the bearing shell is at atemperature slightly above the'melting point of the tinning material sothat as the babbitt and the tin cool and thus harden, the babbitt andtin are fused into a layer which is firmly bonded to the bearing shell;the initially applied babbitt material providing a surface whichfacilitate the application of additional babbitt material by spraying,whereby the babbitt material may be built up to the desired thickness.

The construction designed to carry out the invention will be hereinafterdescribed together with other features thereof.

The invention will be more readily understood from a reading of thefollowing specification and by reference to the accompanying drawingsforming a part thereof, wherein an example of the invention is shown,and wherein:

Figure 1 is an elevation illustrating a bearing shell which has had itsinner bearing surface coated with a tinning material which is bondedthereto.

Figure 2 is a View similar to Figure l, but illustrating the applicationof the initial sprayed layer of babbitt to the tinned surface of thebearing shell.

Figure 3 is a view similar to Figure l, but illustrating the bearingafter additional babbitt has been applied to the tinned surface of thebearing shell.

Figure 4 is a view similar to Figure 3, but illustrating the bearing ofFigure 3 after the babbitt has been machined to a desired thickness.

Figure 5 is an enlarged fragmentary view illustrating a portion ofthebearing shown'in Figure 4.

In the drawings, the numeral 10 designates a conventional bearing shellwhich is substantially semi-cylindri cal and which is adapted to beusedas a bearing for engine shafts and the like when the inner curvedsurface of 16a of the shell 10 is lined with a bearing material. Thebearing shell 16 is made of steel, cast iron, brass or any othermaterial that can be successfully coatedv on its inner surface 100 witha conventional tinning material.

In the present invention, a relatively thin layer of tinning material isinitially applied to the surface ltla of the bearing shell it) by any ofthe known methods wherein the tinning material is effectively bonded tothe bearing shell. For example, the bearing shell 10 can be dipped intoa molten bath of tinning material after the surface 10a to be tinned isproperly cleaned with acid or other suitable material. The tinningmaterial is either tin or an alloy thereof, and usually is an alloycontaining tin and 30% lead. The tinning material is applied in arelatively thin layer and for best results, the thickness of the tinninglayer 12 (Fig. 1) should not exceed .002 inch. After the tinningmaterial layer 12 is formed on the surface ltla, all of the flux andother impurities which might be present as a'result of the tinning stepare removed in the usual manner, for example, by washing with water.

The bearing shell 10 with the tinning material layer 12 thereon is thenheated to a temperature slightly above the melting point of the tinningmaterial so that the tin ning material becomes softened to a semi-solidcondition. The heating of the bearing shell to soften the tinning layer12 can be accomplished with numerous heating devices or methods that arewell known, such as an electric oven or the like.

Preferably, the shell 10 is heated until the tinning material 12.becomes liquefied and then the shell it) is cooled, or is permitted tocool, until the tinning material is just changing to a solid state. Atthis point a thin layer of babbitt metal issprayed onto the tinningmaterial layer 12 (Fig. 2). The spraying of the babbitt material isaccomplished with a metallizing gun G of conventional construction intowhich is fed a babbitt rod 15 and which sprays babbitt material 16 froma nozzle 17 of the gun G. Since the tinning material 12 is in a softenedor semiliquid state, the sprayed particles of babbitt metal 16 actuallypenetrate to someextent and fuse with the tinning material so that thereresults what is believed to be an alloying or fusing of the tinning 12and the babbitt material so that what is referred to as thebabbitt layer18 has its inner portion fused with the tinning material While itsouterportion comprises babbitt material layer 18 as the layers 12 and 18cool. The babbitt layer 13 is relatively thin and is of such thicknessthat the force of shrinkage developed by the applied babbitt as it coolsis insufficient to damage, weaken or otherwise harm the bond between thetinningmaterial layer 12 and the bearing shell 10. For best results, thelayer consisting of the fused tinning and babbittlmaterial should bebetween .004 and .006 inches in thickness.

The spraying of the babbitt 16 to form the initial babbitt layer whichis fused to the tinning material 18 produces a somewhat roughened orirregular external surface 18a due to babbitt particles extendingtherefrom which surface is particularly suitable for the mechanicalbonding of subsequent babbitt material thereto. Thus, after the layer 18has cooled below the point at which is solidifies, then additionalbabbitt material is sprayed onto the initial babbitt layer 18 to buildup the babbitt liner to a predetermined desired thickness. In Fig. 3,the bearing shell is shown after the additional babbitt material hasbeen addedto form the thickness of babbitt 20 on top of the initialbabbitt layer 18. I i 7 Due to the relatively irregular surface 18a ofthe initial babbitt-layer 18, the additional babbitt is bonded to saidlayer by what is believed to be an interlocking or intermingling of'thesprayed babbitt particles, and such bond could be termed a mechanicalbond as distinguished from the fusion bond between the tinning layer. 12and the initial babbitt layer, 18. Additional babbitt material is thenapplied by spraying and since shrinkage is no appreciable factor wherethe material is sprayed an excellent bond between such additionalmaterial and the initial layer is produced. Thus, the required thicknessof babbitt lining is firmly bonded to the bearing shell 10 and theflaking out and other defects in prior known bearings is avoided,whereby increased service is obtained from the bearings of thisinvention;

After the bearing has been completed with a sufiicient application ofbabbitt material (Fig. '3), the external surface of. the babbitt is thenmachined to the required smoothness and thickness in the usual mannerand such bearing in its final machined condition is illustrated in Fig.4. In Figure 5, a portion of the completed bearing is illustrated in thefragmentary sectional view wherein the parts are enlarged to show therelationship more clearly between the bearing shell 10, the tinninglayer 12, the initial babbitt layer 18 which has a portion thereof fusedwith the tinning material and the additional babbitt material 20.

The bearing produced by the above method has numerous advantages overthe prior known babbitt lined bearing since the bearing ofthis inventioneliminates the flaking out of the babbitt fromthe bearing shell afterthe bearing has been in service a short time. Also, the excellentbearing properties of sprayed babbitt are utilized while maintaining anadequate bond with the bearing shell. The sprayed babbitt has a certainamount of porosity which permits it to absorb oil which results inbetter lubrication and further reduces wear and increases the life ofthe bearing.

It should be noted that although the above description of the bearingand the method of making same has been directed. to a bearing of ,thetype ordinarily used for engine shafts and therefore of asemi-cylindrical construction, the invention is applicable to othertypes of bearing body members having different shapes and uses than thatillustrated and described above.

As. heretofore described, the bearing shell with the tinning materiallayer thereon is initiallyheated to a temperature slightly above the,melting point of the tinning material by any suitable means. .It wouldbe possible to carry outthis initial heating step by immersingthebearing shell in a vat of molten babbitt material which is at atemperature of about 75 F. to 100 F. above the melting temperature ofthe babbitt material. Such immersion would function to heat the: bearingshell as well as the face, leaving a very thin layer of fused babbittand tinning material on the shell.

As has been described, the layer of fused babbitt and vention isillustrative and explanatory thereof and various changes in the size,shape and materials, as well as in the details of the illustratedconstruction, may be made, within the scope of the appended-claims,without depart ing from the spirit of the invention.

What is claimed is:

1. In a method for the production of lined bearings, the steps of,heating a bearing shell having a layer of tinning material bondedthereto to a temperature sulficient to soften the tinning material to asemi-solid condition, and then spraying a relatively thin layer ofbabbitt onto the layer of tinning material while the tinning material isin such semi-solid condition to effect a fusion of the babbitt with thetinning material whereby the applied babbitt and the tinning materialare firmly bonded to the bearing shell the layer consising of the fusedtinning and babbitt material being between .004 and .006 inches inthickness, and the inner portion of said babbitt layer is fused withsaid tinning material and the outer portion of said babbitt layercomprises babbitt material only as the tinning and babbitt layers cool,the thickness of the applied babbitt layer being such that the force ofshrinkage developed by the applied babbitt layer as said babbitt layercools is insufficient to affect the bond be tween the tinning materialand the bearing shell.

2. In a method for the production of lined bearings, the steps of,heating a bearing shell having a layer of tinning material bondedthereto to a temperature sufficient to soften the tinning material to asemi-solid condition, and then spraying a relatively thin layer ofbabbitt onto the layer of tinning material while the tinning material isin such semi-solid condition to efiect a fusion of the babbitt with thetinning'material whereby the applied babbitt and the tinning materialare firmly bonded to the bearing shell the layer consising of the fusedtinning and babbitt material being between .004 and .006

inches in thickness, and the inner portion of said babbitt layer isfused with said tinning material and the outer portion of said babbittlayer comprises babbitt material only as the tinning and babbitt layerscool, the thickness of the applied babbitt layer being such that theforce of shrinkage developed by the applied babbitt layer as saidbabbitt layer cools is insufficient to affect the bond be tween thetinning material and the bearing shell, and" thereafter sprayingadditional babbitt material to the initial babbitt layer to build up abearing surface of desired thickness.

3. In a method of lining a bearing shell having a layer of tinningmaterial bonded thereto, the steps of, heating tinning material andwould bring about some fusionof babbitting material with the tinningmaterial. Upon removal of the shell from the vat of molten babbittmaterial, the surplusbabbitt material is wiped from the surthe bearingshell to a temperature slightly above the melting point of the tinningmaterial to liquefy the tinning material, then permitting the tinningmaterial to cool, and then spraying a relatively thin layer of babbittonto the .layer of tinning material. at the time said tinning materialis just changing from a liquid to a solid state whereby the appliedbabbitt and the tinning material are firmly bonded to the bearing shellthe layer consising of the fused tinning and babbitt material beingbetween .004 and .006 inches in thickness, and the inner portion of saidbabbitt layer is fused with said tinning material and the outer portionof said babbitt layer comprises babbitt material only as the tinning andbabbitt layers cool, the thickness of the applied babbitt layer beingsuch that the force of shrinkage developed by the applied babbitt layeras said babbitt layer cools is insufiicient to affect the bond betweenthe tinning material and the bearing shell,

4. In a method of lining a bearing shell having a layer of tinningmaterial bonded thereto, the steps of, heating the bearing shell to atemperature slightly above the melting point of the tinning material toliquefy the tinning material, then permitting the tinning material tocool, and

then spraying a relatively thin layer of babbitt onto the layer oftinning material at the time said tinning material is just changing froma liquid to a solid state whereby the applied babbitt and the tinningmaterial are firmly bonded to the bearing shell the layer consising ofthe fused tinning and babbitt material being between .004 and .006inches in thickness, and the inner portion of said babbitt layer isfused with said tinning material and the outer portion of said babbittlayer comprises babbitt material only as the tinning and babbitt layerscool, the thickness babbitt layer cools is insuificient to aflfect thebond between the tinning material and the bearing shell, and thereafterspraying additional babbitt material upon the initial babbitt layer tobuild up a bearing surface of desired thickness.

References Cited in the file of this patent UNITED STATES PATENTS1,956,467 Palm Apr. 24, 1934 2,101,759 Smart Dec. 7, 1937 2,149,826Albertson Mar. 7, 1939 2,224,789 Queneau et al. May 13, 1941 2,314,902Shepard Mar. 30, 1943 2,325,071 Murray July 27, 1943 2,388,019Strickland Oct. 30, 1945

1. IN A METHOD FOR THE PRODUCTION OF LINED BEARING THE STEPS OF, HEATINGA BEARING SHELL HAVING A LAYER OF TINNING MATERIAL BONDED THERETO TO ATEMPERATURE SUFFICIENT TO SOFTEN THE TINNING MATERIAL TO A SEMI-SOLIDCONDITION, AND THEN SPRAYING A RELATIVELY THIN LAYER OF BABBITT ONTO THELAYER OF TINNING MATERIAL WHILE THE TINNING MATERIAL IS IN SUCHSEMI-SOLID CONDITION TO EFFECT A FUSION OF THE BABBITT WITH THE TINNINGMATERIAL WHEREBY THE APPLIED BABBITT AND THE TINNING MATERIAL ARE FIRMLYBONDED TO THE BEARING SHELL THE LAYER CONSISTING OF THE FUSED TINNINGAND BABBITT MATERIAL BEING BETWEEN .004 AND .006 INCHES IN THICKNESS,AND THE INNER PORTION OF SAID BABBITT LAYER IS FUSED WITH SAID TINNINGMATERIAL AND THE OUTER PORTION OF SAID BABBITT LAYER COMPRISES BABBITTMATERIAL ONLY AS THE TINNING AND BABBITT LAYERS COOL, THE THICKNESS OFTHE APPLIED BABBITT LAYER BEING SUCH THAT THE FORCE OF SHRINKAGEDEVELOPED BY THE APPLIED BABBITT LAYER AS SAID BABBITT LAYER COOLS ISINSUFFICIENT TO AFFECT THE BOND BETWEEN THE TINNING MATERIAL AND THEBEARING SHELL.